[aat] Simplify complex condition
Based on https://github.com/RazrFalcon/rustybuzz/discussions/79#discussioncomment-6960324
diff --git a/src/hb-aat-layout-common.hh b/src/hb-aat-layout-common.hh
index 7d53c35..672f80e 100644
--- a/src/hb-aat-layout-common.hh
+++ b/src/hb-aat-layout-common.hh
@@ -851,43 +851,41 @@
*
* https://github.com/harfbuzz/harfbuzz/issues/2860
*/
- const EntryT *wouldbe_entry;
- bool safe_to_break =
- /* 1. */
- !c->is_actionable (this, entry)
- &&
- /* 2. */
- (
- /* 2a. */
- state == StateTableT::STATE_START_OF_TEXT
- ||
- /* 2b. */
- (
- (entry.flags & context_t::DontAdvance) &&
- next_state == StateTableT::STATE_START_OF_TEXT
- )
- ||
- /* 2c. */
- (
- wouldbe_entry = &machine.get_entry (StateTableT::STATE_START_OF_TEXT, klass)
- ,
- /* 2c'. */
- !c->is_actionable (this, *wouldbe_entry)
- &&
- /* 2c". */
- (
- next_state == machine.new_state (wouldbe_entry->newState)
- &&
- (entry.flags & context_t::DontAdvance) == (wouldbe_entry->flags & context_t::DontAdvance)
- )
- )
- )
- &&
- /* 3. */
- !c->is_actionable (this, machine.get_entry (state, StateTableT::CLASS_END_OF_TEXT))
- ;
- if (!safe_to_break && buffer->backtrack_len () && buffer->idx < buffer->len)
+ const auto is_safe_to_break_extra = [&]()
+ {
+ /* 2c. */
+ const auto wouldbe_entry = machine.get_entry(StateTableT::STATE_START_OF_TEXT, klass);
+
+ /* 2c'. */
+ if (c->is_actionable (this, wouldbe_entry))
+ return false;
+
+ /* 2c". */
+ return next_state == machine.new_state(wouldbe_entry.newState)
+ && (entry.flags & context_t::DontAdvance) == (wouldbe_entry.flags & context_t::DontAdvance);
+ };
+
+ const auto is_safe_to_break = [&]()
+ {
+ /* 1. */
+ if (c->is_actionable (this, entry))
+ return false;
+
+ /* 2. */
+ // This one is meh, I know...
+ const auto ok =
+ state == StateTableT::STATE_START_OF_TEXT
+ || ((entry.flags & context_t::DontAdvance) && next_state == StateTableT::STATE_START_OF_TEXT)
+ || is_safe_to_break_extra();
+ if (!ok)
+ return false;
+
+ /* 3. */
+ return !c->is_actionable (this, machine.get_entry (state, StateTableT::CLASS_END_OF_TEXT));
+ };
+
+ if (!is_safe_to_break () && buffer->backtrack_len () && buffer->idx < buffer->len)
buffer->unsafe_to_break_from_outbuffer (buffer->backtrack_len () - 1, buffer->idx + 1);
c->transition (this, entry);
